NDA2024MathematicsBinomial TheoremActual
Paragraph: Let (8+3 7 )²⁰= U + V and (8-3 7 )²⁰= W , where U is an integer and 0 Question: What is V + W equal to?
Options
- A8
- B4
- C2
- D1
Correct answer
D. 1
Step-by-step solution
We have, (8+3 7 )²⁰= U + V ....(i) and (8-3 7 )²⁰= W ....(ii) Here, o < W < 1 Now, adding equation (i) & (ii), we have, aligned & U + V + W =(8+3 7 )²⁰+(8-3 7 )²⁰ & =2 [ ²⁰ C ₀ 8²⁰+ ²⁰ C ₂ 8¹⁸ (3 7 )^2+ .+(3 7 )²⁰ ] aligned R.H.S. is an even number. Also, o < V < 1, o < W < 1 and U is an integer V + W is an integer V + W =1 So, V+W=1